Sometimes the best advice is the simplest.
Just look at the teachings of Buddha. The quote above, written sometime between the 6th and 4th century, B.C., can still be applied today, for just about any interaction.
But especially for sales.
Think about those three simple sentences with regard to speaking with a potential or existing customer -
Is it true?
Is it necessary?
Is it kind?
Are you telling the truth about your product or service? Or are you embellishing, or worse, lying, just to make a sale?
Is every word out of your mouth necessary to the conversation, worth speaking? Or are you just spewing your facts and figures and not listening to who's in front of you?
And the last - what I feel the most important - are you doing the right thing? Are you being kind in your delivery, your attention, your sincerity, and ultimately, your goal with meeting with and talking with your customer. Are you okay with helping that customer, even if it means NOT making a sale?
Those three sentences are usually referred to as "The Three Gates," and there have been other, similar versions and even additional gates attributed to many scholars. However, the meanings are the same.
Be truthful.
Be necessary in your words
Be kind.
Do those three things and you will have quite the fulfilling sales life.